Study On Multi-layer And Multi-pass Welding Of Thick And Medium Plate Based On MotoSimEG-VRC

As a centralized embodiment of modern intelligence,welding robots are playing its indispensable role.It is the dream of several generations to completely replace humans with robots.Therefore,breaking through the key technology of intelligent welding is not only a hotspot of future research,but also an urgent demand at the moment.Up to now,according to statistics,most of the first generation of "teaching reproduction" robots are used in production,both at home and abroad,which have a relatively low degree of intelligence.However,the actual situation is that in the general welding process,the deviation of the weld and the teaching track is often caused by the factors such as the change of the staggered edge deformation,the change of the gap,the machining error of the artifact and the assembly error.The trajectory deviation has no adaptability,which will eventually lead to a decline in welding quality.This is facing the problem of re-teaching,and it is difficult to adapt to modern high-quality,highprecision,high-efficiency production lines of enterprises,which limits its application in many fields.In order for the robot to calmly cope with various unexpected factors in the welding process,it is urgently necessary to improve the robot's adaptability and intelligence through technological innovation.This article uses the MotoSimEG-VRC offline programming software to work with a welding robot to form an "offline programming" type welding robot system.The "offline programming" type welding robot has the following advantages:(1)the welding production line does not need to be suspended,can run continuously and improves production efficiency;(2)can meet the production needs of small batches of complex products;(3)The robot motion program is programmed in advance,no teaching is required,errors are reduced,and there is no need to worry about collision between the robot and the artifact;(4)No personnel are present during the welding process,which can be used in deep water,space,and nuclear radiation.operating.The purpose of this paper is to use this system to weld test plates of different specifications,analyze its feasibility,and try to find out the corresponding optimal filling strategy to guide the actual welding production.In this paper,five custom filling strategies are designed for 16 mm and 10 mm thick test plates,each of which contains a filling strategy for transverse welding.The position planning of each welding bead in each filling strategy is carried out by using the method of simplifying the welding bead.The position offset of each welding bead and the end attitude of the welding gun are calculated.At the same time,the robot coping strategy is designed for the groove with deviation,including the groove gap change The coping strategies of chamfering and groove bottom staggering.Based on the planned bead trajectory,offline programming software is used for simulation.First,a simulation model was created,and then a robot motion program was designed for the multi-layer multi-pass welding process.In the process,the temperature field simulation of the welding was used to control the inter-layer temperature to set the robot's residence time.Finally,the robot's motion path was successfully simulated.After comparison,it is basically the same as the trajectory plan.After the experiment,the metallographic structure and mechanical properties of each welded joint were observed.The micro-hardness and tensile strength of each joint area were mainly compared.The results show that the # 1-3 and # 2-4 joints have excellent mechanical properties.